To Tobi, James and Don. Thanks a lot for your kind comments. I'm very glad you like the pyrite.

There are from my point of view several reasons to like that specimen:
- It has a nice shape with that large main crystal sitting on the top.
- The matrix is also pyrite, though this may lower the colour contrast, the specimen looks very classy and I guess this are also two generations (?) of pyrite growth which would make this paragenesis even more interesting.
- There are both black and white minerals on it which compensate that there's actually not much contrast.

There are from my point of view several reasons to like that specimen:
- It has a nice shape with that large main crystal sitting on the top.
- The matrix is also pyrite, though this may lower the colour contrast, the specimen looks very classy and I guess this are also two generations (?) of pyrite growth which would make this paragenesis even more interesting.
- There are both black and white minerals on it which compensate that there's actually not much contrast.
Conclusion: A very fine and presentable pyrite specimen :)

Tobi, thanks once again, now for spending your valuable time in such a long and detailed review. I think your analysis is very interesting.

This specimen is a chain of three-dimensional and untwinned quasi octahedral {111}, reddish brown color, copper crystals stacked one on top of another. The crystals show very well defined faces and edges, which is somewhat unusual with this species. There also is a natural deep black oxidation patina on the lateral and back sides that I think might be tenorite (CuO) rather than cuprite.
Field collected in year 2009.
Overall size: 63 mm x 10 mm. Major crystal size: 8.5 mm wide.
Weight: About 13 g.

Indeed a very (!) good sample of copper with remarkably well defined crystals, the colour change makes it even more attractive. Usually I don't like native copper specimens, but this one is an eyecatcher, good choice.

Indeed a very (!) good sample of copper with remarkably well defined crystals, the colour change makes it even more attractive. Usually I don't like native copper specimens, but this one is an eyecatcher, good choice.

A sharp and well defined tetrahedrite tetrahedron {111} sitting on top of two lustrous and finely striated cubic {100} pyrite crystals, accompanied with a lot of colorless quartz and several sphalerite crystals here and there. Both pyrite crystals show a face along an edge that probably belongs to the pyritohedron habit {210}. Overall size: 77 mm x 71 mm x 54 mm. Tetrahedrite crystal: 24 mm on edge. Major pyrite crystal: 26 mm on edge. Weight: 273 g.

Actually a member of the series tennantite-tetrahedrite. So it might be from a Sb-rich tennantite to an As-rich tetrahedrite, somewhere between.

This specimen was involved in at least five generations. It is evident that the pyrite crystals were the first to grow. Then came the sphalerite and next the tetrahedrite, since a small crystal of the latter is placed on a crystal of the former. Finally the quartz grew over all of them. But still a fifth generation had to take place because about a dozen small pyrite cubes can be seen perched on the quartz crystals.

Ferberite, quartz
Tabular black ferberite crystals associated with each other like pages in a half open book, with several white quartz crystals at the bottom. Yaogangxian Mine, Yizhang, Chenzhou Prefecture, Hunan Province, China.

I actually do not collect ferberite and I never had any interest in that mineral ... but that specimen is really appealing: Well-defined crystals, a fine shape of the whole specimen, a nice colour contrast - all in all a very beautiful specimen and a fine addition to your collection, congratulations :-)

This early morning this topic has reached the magic number of 500,000 views. I think a half million is a lot for a mere medium quality collection, so I feel a must to send a big thank you to all of you who have spent your valuable leisure time browsing my pages. And especially to Jordi Fabre for making it possible. I hope more photos will come in in the not distant future._________________Yesterday is history. Tomorrow is a mystery. Today is a gift. That's why it's called the present.

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